Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
Untethered iOS 6 Jailbreak For iPhone 5 Confirmed
Some people had lost some hope in seeing a Jailbreak for iOS 6 for the iPhone 5 but it appears that hope has been restored in the Jailbreak community tonight from well known jailbreak planetbeing after he took to Reddit today to explain the situation of the Jailbreak. planetbeing claims he has an untethered jailbreak for iOS 6.0.2 for the iPhone 5.
planetbeing has said he is going to wait until Apple release iOS 6.1 as the update could patch the bug used for the jailbreak which means the jailbreak would not work.